In the past there have been numerous types of devices which have been utilized for persons having an injured or broken arm such as the well-known plaster cast. This invention is of a lower arm brace which is adapted to be secured about the arm of a wearer and wherein a first and a second or, rather, an outer and an inner segment are provided for clamping or clam shell type interengagement with one another about the arm of a wearer to apply pressure to the flesh so as to support the lower arm bone. The device includes an adjustable means to adjust the amount of pressure which is applied by the two segments when in nested relation with one another and about the arm of a wearer.